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There has been a rapid advancement in wireless sensor network (WSN) technology in the past decade and its application in structural monitoring has been the focus of several research projects. The evaluation of the newly developed hardware platform and software system is an important aspect of such research efforts. Although much of this evaluation is done in the laboratories and using generic signal processing techniques, it is important to validate the system for its intended application as well. In this paper the performance of a newly developed accelerometer sensor board is evaluated by using the data from a beam-column connection specimen with a local damage detection algorithm. The sensor board is a part of a wireless node that consists of the Imote2 control/communication unit and an advanced antenna for improved connectivity. A scaled specimen of a steel beam-column connection is constructed in ATLSS center at Lehigh University and densely instrumented by synchronized networked systems of both traditional piezoelectric and wireless sensors. The column ends of the test specimen have fixed connections, and the beam cantilevers from the centerline of the column. The specimen is subjected to harmonic excitations in several test runs and its acceleration response is collected by both systems. The collected data is then used to estimate two sets of system influence coefficients with the wired one as the reference baseline. The performance of the WSN is evaluated by comparing the quality of the influence coefficients and the rate of convergence of the estimated parameters.

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Damage prognosis for structural health monitoring is a challenging and complex research topic in civil engineering. Early and accurate damage detection is essential to maximizing the useful life of structures. The use of densely clustered sensor networks provides promising applications in the analysis of structural components and identification of local damage. The proposed localized damage detection method utilizes a linear regression analysis to monitor changes in the linear behavior of a structure with the onset of damage. The structural responses at various sensor locations along a structure are compared to those of other locations and pair-wise influence coefficients are estimated. These coefficients serve as damage indicators when damaged values are compared to healthy-state values. By statistically comparing the change in influence coefficients, structural damage can be accurately and effectively identified. The method is verified using simulations and an experimental prototype of a local beam-column connection, as well as a simulated model of a twospan bridge girder.